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  <script>
    function minimumFinishTime(tires, changeTime, numLaps){3
    // one[i]: 使用同一个轮胎跑i圈的最短时间
    // 多跑一圈的时间<=重新换胎跑一圈的时间 估计一下最多一次跑19圈左右
    const one = new Array(20).fill(Infinity)
    for(const [f, r] of tires) {
        for(let i = 1, cost = 0; f * (r ** (i-1)) <= f + changeTime; i++) {
            cost += f * (r ** (i-1))
            one[i] = Math.min(one[i], cost)
        }
    }
    // dp[i]: 可换胎跑i圈的最短时间
    const dp = new Array(numLaps+1).fill(Infinity)
    dp[0] = 0
    for(let i = 1; i<=numLaps; i++) {
        // 最多跑19圈
        for(let j = 1, loops = Math.min(i, 19); j<=loops; j++) {
            dp[i] = Math.min(dp[i], dp[i-j] + changeTime + one[j])
        }
    }
    return dp[numLaps] - changeTime
};
console.log(minimumFinishTime([[2,3],[3,4]],5,4));
  </script>
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